The present invention relates in general to a support bracket for mounting a headlamp and a hood support to a grille opening reinforcement of an automotive vehicle, and, more specifically, to a breakaway support structure for managing reaction forces when the hood is impacted during a collision (e.g., with a pedestrian).
Automotive hood structures require support posts (often called bump-stops) along the sides of an engine compartment, e.g., at the front outboard corners. The bump-stops are mounted to a body reinforcement structure, such as a grille-opening reinforcement (GoR), and are typically adjustable in height in order to maintain fit and finish margins with the surrounding body closure structures. The forward areas of the hood are suspended over headlamp structures which are themselves affixed to the reinforcement structure. In the conventional mounting of hood bump-stops and headlamp modules, there has been an issue of the hood structure having a greater than desired resistance against deformation induced by a collision (most specifically by a pedestrian head impactor). In such a situation, impact speed and mass of the impactor may not be high enough to overcome the combined break-away resistance of all the mounting components that are supporting the hood which in turn produces high acceleration.
The foregoing problem may be amplified by a particular vehicle styling in which a relatively flat hood surface is closely spaced to the headlamps. The resulting limited stroke zone together with the breakaway resistance of the headlamp and the resilience of the hood material itself may provide a hood impact strength that results in undesirably high acceleration being imparted to the impactor.
Breakaway connections have been used which limit the impact resistance at each support/mounting location. However, each support and mounting structure needs to maintain sufficient strength and robustness in order to perform its intended function during normal use over a long service lifetime. Since the hood depends on a plurality of different supporting structures, the breakaway forces for several of them may come into play during a particular impact. The summing of the resistance to breakage of the several components makes it difficult to achieve the desired response during a pedestrian impact.